Motor-driven, hand-guided hedge cutters include two shearing blades running in mutually opposite directions. In such hedge cutters, eccentric drives are used in addition to connecting rod drives, wherein a rotatingly driven eccentric wheel is provided which has two eccentrics mutually offset by 180°. These two eccentrics engage in connecting links of the two shearing blades whereby the shearing blades are oscillatingly driven in mutually opposite directions.
In a known configuration, the two shearing blades including their two connecting links lie directly one atop the other. The two eccentrics are arranged on the same side of the corresponding drive wheel and engage in one of the two connecting links. This facilitates the exchange of the shearing blades, because they can be pulled off the eccentric drive when the gear housing is open, without having to disassemble the eccentric wheel itself.
In practice, however, it has been shown that, when developing large shearing forces, the drive eyes of the shear blades defined by the connecting links can axially lift off the eccentrics, so that the drive of the shear blade arranged remotely from the drive wheel is interrupted. The shearing blade which lies between the above-mentioned shear blade and the drive wheel can also tend to lift up. In this case, both eccentrics can engage simultaneously in the assigned connecting link. This leads to a blockage of the entire hedge trimmer drive.
To prevent lift-up, a cover can be applied which holds the connecting links of the shear blades in their axial position on the eccentric drive with a counterforce. However, the two shearing blades are stacked one atop the other. For this reason, such a cover can apply a holding force only upon the outer shearing blade. This shearing force is then transmitted to the shearing blade lying underneath. This leads to a considerable increase in friction between the two shearing blades and therefore to an unwanted increase in temperature in the eccentric drive, which impairs the permanent lubrication. The lubricant can turn liquid and escape or burn. In total, the wear properties of this arrangement are not satisfactory.